The invention relates to a switching mode power supply device comprising at least one MOS power transistor made on an integrated circuit and operating in switching mode, the drain and the source of said at least one MOS power transistor being connected, via connecting members having a non-null inductance, to one or several external circuits to said integrated circuit. According to the invention, the device further comprises a limiter circuit able to limit the current variations in at least one of said connecting members during the switching of said MOS power transistor. This limiter circuit enables to maintain the drain-source voltage of the MOS power transistor below a predetermined threshold value when it commutes.